[presubmit] Add check to prevent new metadata in OWNERS files.

Presubmit check added in crrev.com/c/2582566

Bug: 1113033
Change-Id: I09802343bd11d3f5f044cda4cea3aa8e58c8c398
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2583464
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Auto-Submit: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Cr-Commit-Position: refs/heads/master@{#836821}

PRESUBMIT.py

@@ -4388,6 +4388,9 @@ def ChecksCommon(input_api, output_api):
   results.extend(
       input_api.canned_checks.CheckOwnersDirMetadataExclusive(
           input_api, output_api))
+  results.extend(
+      input_api.canned_checks.CheckNoNewMetadataInOwners(
+          input_api, output_api))
 
   for f in input_api.AffectedFiles():
     path, name = input_api.os_path.split(f.LocalPath())